Не отображаются JRadioButton, что я упустил?

public UserInterface(){
          
            setBounds(100,35,500,680);
            setResizable(false);
            setTitle("IQ test");
            setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

            JPanel panel = new JPanel();
            panel.setLayout(null);

            JButton prevQ = new JButton("<<<");
            prevQ.setBounds(120, 615, 60, 20);
            panel.add(prevQ);

            JButton nextQ = new JButton(">>>");
            nextQ.setBounds(320, 615, 60, 20);
            panel.add(nextQ);

            JButton chButton = new JButton("Check Answer");
            chButton.setBounds(190, 610, 120, 30);
            panel.add(chButton);

            JTextField input = new JTextField("Answer here...");
            input.setBounds(300, 550, 140, 20);
            panel.add(input);

            JLabel question = new JLabel("Something");
            question.setBorder(new javax.swing.border.LineBorder(new java.awt.Color(102, 102, 102), 1, true));
            question.setBounds(10, 10, 475, 70);
            panel.add(question);

            ButtonGroup group = new ButtonGroup();

            JRadioButton radio1 = new JRadioButton("Select 1");
            JRadioButton radio2 = new JRadioButton("Select 2");
            JRadioButton radio3 = new JRadioButton("Select 3");
            JRadioButton radio4 = new JRadioButton("Select 4");
            JRadioButton radio5 = new JRadioButton("Select 5");
            JRadioButton radio6 = new JRadioButton("Select 6");
            radio1.setBounds(250, 450, 0, 0);
            radio2.setBounds(250, 430, 0, 0);
            radio3.setBounds(250, 410, 0, 0);
            radio4.setBounds(250, 390, 0, 0);
            radio5.setBounds(250, 370, 0, 0);
            radio6.setBounds(250, 350, 0, 0);
            group.add(radio1);
            group.add(radio2);
            group.add(radio3);
            group.add(radio4);
            group.add(radio5);
            group.add(radio6);
            panel.add(radio1);
            panel.add(radio2);
            panel.add(radio3);
            panel.add(radio4);
            panel.add(radio5);
            panel.add(radio6);
            
            JLabel img = new JLabel();
            img.setBounds(10, 80, 230, 520);
            img.setIcon(new javax.swing.ImageIcon("Снимок.png"));
            img.setBorder(new javax.swing.border.LineBorder(new java.awt.Color(102, 102, 102), 1, true));
            panel.add(img);

            getContentPane().add(panel);
     
        }